Easy to fill and use
Tap water won’t kill you but it does contain chlorine, lime-scale and other organic impurities. There is a fair amount of evidence that it contains anti-depressants and female-hormones from the pill.
Nowadays I tend to distil my water but I like this Britta device as it contains far more water than a jug, and makes it much more practical to use filtered water for all your needs: from cold and hot drinks, to water to boil or steam your vegetables.